We present an on-line study showing different sources of lexical activation during sentence comprehension, distinguishing in this respect between reflexive syntactic and less temporarily constrained nonsyntactic sources. Specifically, we show that both the syntactic process of gap filling and a nonsyntactic end-of-sentence effect can be measurable in real time and can be temporally separated. The distinction between activation sources provides a new perspective on real-time sentence comprehension in aphasia and accounts for the disparate results reported in the literature.